In the past, defoaming equipment was used primarily in the defoaming of carpets after a cleaning process. This was accomplished by vacuuming foam into a holding tank incorporated in a carpet cleaning machine and passively mixing it with some type of liquid defoamer. An example of such a system appears in U.S. patent application Ser. No. 5,813,086. This was done to break down the detergent in a simple and inexpensive manner, thereby reducing the space required to contain the spent liquid.
Current generations of Blast and Decontamination Foams are considerably thicker and more stable than industrial cleaning foams, are much harder to break down, and readily produce copious amounts of additional foam when agitated; all aspects that render conventional defoaming techniques impractical. These new foams include, for example, those described in U.S. patent application Ser. No. 6,405,626, issuing on Jun. 18, 2002 and titled “Decontaminating and Dispersion Suppressing Foam Formulation”, and in U.S. patent application Ser. No. 6,553,887, issuing on Apr. 29, 2003 and titled “Foam Formulations”. There is a need for a method of, and an apparatus for breaking down and collecting these new foams.
These new foams may be employed in a variety of manners. For example, Blast Mitigation Structures have been developed such as those described in U.S. patent application Ser. No. 6,439,120, issuing on Aug. 27, 2002, and titled “Apparatus and Method for Blast Suppression”. In short, this patent describes the process of placing a fabric tent-like structure over a suspect package, filling the tent with Blast Mitigation Foam, and detonating the suspect package. The tent-like structure and Blast Mitigation Foam absorb the energy of the explosion and contain any contaminants. The contents of the Blast Mitigation Structure must then be removed and disposed of, while minimizing the risk of exposing technicians and/or the environment to hazardous materials. This is also preferably done without coating the Blast Mitigation Structure with defoaming compound, which might compromise the use of the Blast Mitigation Structure in the future. Presently, there are no effective ways of doing this.
Similarly, various foams may be used to decontaminate vehicles or surface areas exposed to chemical, biological or radiological components or similar threats. No effective means or methods of collecting such decontaminant foams are currently available.
There is therefore a need for a method of and apparatus for defoaming, provided with consideration for the problems outlined above.